This invention relates generally to a method of forming a seal assembly around a shaft, and more particularly to a method of forming a seal assembly around a shaft of a roller assembly of a track type work machine.
Track type work machines typically include a track chain disposed around an idler, a drive sprocket, and a number of roller assemblies interposed the drive sprocket and the idler. Each roller assembly includes a seal assembly having a pair of seal members urged together so as to form a sliding seal interface therebetween. The seal interface functions to ensure that debris (e.g. dirt) present in the environment of the work machine does not enter the roller assembly. The seal interface also functions to maintain a lubricant within the roller assembly.
In order for the seal interface to perform the above described functions properly, the seal members should be urged together so as to create a proper load therebetween. For example, if the force utilized to urge the seal members together is too low then the load therebetween could be reduced to the point where the seal interface does not effectively prevent debris from entering the interior of the roller assembly. On the other hand, if the force utilized to urge the seal members together is too great, then the load therebetween could be increased to the point where too much heat is generated at the interface of the two seal members as the roller assembly is utilized. Both of the above described scenarios can cause maintenance problems.
One way of controlling the load generated between the seal members is to fix a support member at a predetermined position on a shaft of the roller assembly. Fixing the support member in the above described manner then urges the seal members together with a force which is partially controlled by the predetermined position on the shaft at which the support member is fixed. However, a problem with this approach is that the load generated between the two seal members can still vary a significant amount due to the cumulative effect of the mechanical tolerances of the various components which make up the seal assembly.
The present invention is directed to overcoming one or more of the problems or disadvantages associated with the prior art.
In accordance with one embodiment of the present invention there is provided a method of forming a seal assembly around a shaft. The seal assembly has a first support member, a first seal member having a first seal face, a second seal member having a second seal face, and a second support member. The first support member, the first seal member, the second seal member, and the second support member are all disposed around the shaft such that the first seal member and the second seal member are (i) interposed the first support member and the second support member and (ii) the first seal face is in contact with the second seal face. The method includes (a) urging the first seal member against the second seal member so as to produce a load between the first seal face and the second seal face, (b) measuring the load produced between the first seal face and the second seal face during the urging step, and (c) securing the first support member to the shaft when a predetermined load value between the first seal face and the second seal face is attained so as to fix the relative position between the first seal member and the second seal member such that the predetermined load is substantially maintained between the first seal face and the second seal face.
In accordance with another embodiment of the present invention there is provided a method of forming a seal assembly around a shaft. The seal assembly has a first support member, a first seal member having a first seal face, a second seal member having a second seal face, and a second support member. The method includes (a) positioning the first support member, the first seal member, the second seal member, and the second support member in a fixture such that the first seal member and the second seal member are interposed the first support member and the second support member, (b) positioning a first ram in contact with the first support member, (c) moving the first support member a distance D1 relative to the second support member so as to cause the first seal member to be urged against the second seal member such that a load is produced between the first seal face and the second seal face, (d) locating (i) a second ram in contact with the first support member and (ii) a third ram in contact with the second support member, (e) fixing the relative position between the second ram and the third ram such that an end of the second ram is spaced apart from an end of the third ram by a distance D2 which is substantially equal to the distance D1, (f) positioning the first support member, the first seal member, the second seal member, and the second support member relative to the shaft so that (i) the first support member, the first seal member, the second seal member, and the second support member are disposed around the shaft and (ii) the first seal member and the second seal member are interposed the first support member and the second support member, (g) placing the fixed second and third rams relative to the shaft, the first support member, and the second support member so that (i) the second ram is in an opposing relationship with a wall segment of the first support member and (ii) the third ram is in an opposing relationship with a wall segment of the second support member, and (h) advancing the fixed second and third rams along a longitudinal axis of the shaft so that (i) the third ram contacts the wall segment of the second support member, (ii) the second ram contacts the wall segment of the first support member, and (iii) the second ram moves the first support member relative to the second support member a distance D3. The distance D3 is substantially equal to the distance D1 and the distance D2.
In accordance with yet another embodiment of the present invention there is provided a method of manufacturing a work machine which includes a roller assembly having (i) a rim with a receptacle and a passageway defined therein and (ii) a shaft positioned within the passageway. The method includes (a) positioning a first support member, a first seal member, a second seal member, and a second support member in a fixture such that the first seal member and the second seal member are interposed the first support member and the second support member, (b) positioning a first ram in contact with the first support member, (c) moving the first support member a distance D1 relative to the second support member with the first ram so as to cause the first seal member to be urged against the second seal member such that a load is produced between a first seal face defined on the first seal member and a second seal face defined on the second seal member, (d) locating (i) a second ram in contact with the first support member and (ii) a third ram in contact with the second support member, (e) fixing the relative position between the second ram and the third ram such that an end of the second ram is spaced apart from an end of the third ram by a distance D2 which is substantially equal to the distance D1, (f) positioning the first support member, the first seal member, the second seal member, and the second support member relative to the shaft so that (i) the first support member, the first seal member, the second seal member, and the second support member are disposed around the shaft and located within the receptacle and (ii) the first seal member and the second seal member are interposed the first support member and the second support member, (g) placing the fixed second and third rams relative to the first support member, and the second support member so that (i) the second ram is in an opposing relationship with a wall segment of the first support member and (ii) the third ram is in an opposing relationship with a wall segment of the second support member, and (h) advancing the fixed second and third rams along a longitudinal axis of the shaft so that (i) the third ram contacts the wall segment of the second support member, (ii) the second ram contacts the wall segment of the first support member, and (iii) the second ram moves the first support member relative to the second support member a distance D3. The distance D3 is substantially equal to the distance D1 and the distance D2.